Friday on CNBC's"Power Lunch," Marc Harris, head of global research at RBC, said that the uncertainty is the biggest problem currently facing the U.K and Europe.

"The sheer uncertainty about the process by which the U.K. will leave the E.U. is a dominant factor in assessing the economic outlook. We now forecast 0 percent GDP growth [U.K.]…Although automatic stabilizers in the government sector are likely to be allowed to operate naturally, neither that nor the boon from the exchange rate are expected to offset the drop in business spending or a moderation in private consumption growth."